Compression Performance Tuning in Systems Management Server

MORE INFORMATION

• During a package compression, a block of data is submitted to the compression algorithm and this call returns a compressed block. A large number of these calls can take a large amount of CPU time, so we have a timer that allows Systems Management Server to yield the processor for the specified amount of time. The default is 75 milliseconds. In addition, you can set a Registry entry under:

        HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS\Compression\ 
  
        "Yield Time" (DWORD) [this is in milliseconds of yield time per
        compression block]
  						

  If compression appears to monopolize your system, try setting this to 100 or 125. For systems with lots of RAM and CPU power, values of 1-20 might be usable, and this would speed up compression somewhat.
• There are 7 levels of compression (1 through 7); a level of 1 (default) providing the least compression and greatest speed, and a level of 7 providing maximum compression and taking additional time. This value is located at:

        HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS\Compression\ 
  
        "Compression Level" (DWORD)
  						

  In addition to the degree of compression desired, compression can be disabled by setting the value below to "No". The default is "Yes".

        HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS\Compression\ 
  
        "Enable Compression" (REG_SZ)
  						

  Two-to-three megabytes (M) of memory resource can be saved by disabling compression; however, greater disk space will be required to store the package files because they will not be compressed.
• Decompression Buffer size:

        HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS\Compression\ 
  
        "Decompression Buffer Size (Log2 Value)" (DWORD)
  						

  This value specifies the number of buffers to be used when decompressing a package file. It defaults to 15 and can be set to a value of 1 through 31; however, for Systems Management Server version 1.0, values greater than 15 are ignored.